This invention relates in general to metal working machines and, more particularly, to a roll forming machine.
Roll forming machines are used to form sheet material into variously shaped products and generally offer significant economic advantages over other types of fabrication processes. The material is formed by feeding it between pairs of vertically aligned rollers which progressively impart the desired shape to the material as it is pulled from the input to the output end of the machine by rotation of the rollers.
Because of the large cost of roll forming machines and limited floor space in a shop, it is desirable that each machine be easily adaptable to perform various roll forming processes. The construction of conventional roll forming machines, however, makes it extremely difficult to properly set up and adjust the machines, thus reducing the amount of time that they are available for production. As one example, individual uprights are typically used for housing each pair of upper and lower rollers and exact alignment of each housing along the length of the machine is necesary to prevent binding or slipping of the material being formed. Properly aligning each housing, however, can be an extremely time consuming operation as large numbers of these roller and housing sets are required for most forming operations.
In order to reduce the time involved in changing the tooling on these machines, a group of roller and housing sets are often mounted together on a removable platform or raft. These rafts may then be removed and replaced by a raft with the desired tooling when a different forming operation is to be conducted. While this reduces the time required for changing over the machine, it requires a significant capital investment in duplicate castings and rollers.
Other construction features of conventional machines also add significantly to the cost of the machines. Large torsional forces are exerted on the machine by the forming operations and the various machine components are typically constructed from heavy cast metal to prevent warping or failure of the machine. Components such as the support platform and the upright housings must also be machined to exact tolerances to ensure tht the rollers are properly aligned. This type of construction, while necessary for conventional roll forming machine designs, adds significantly to the cost of such machines.
The use of heavy cast metals in the construction of these machines also adds significantly to their weight. This presents an added problem in that it is often desirable that the machines be relocated within the shop such as in those instances when two or more machines placed end to end would increase the efficiency of a roll forming process. The large weight of these machines, however, makes movement of the machines difficult and they are generally left in a fixed location in the ship. In addition, the ship floor must be reinforced to provide adequate support for the machines.